Boring machine



M y 17, 1938. l. H. lHM ET AL. 2,117,327

BORING MACHINE Filed March 12, 1935 2 Sheets-Sheet l [Fig 2 I H InVen'l-m's IVAN H. ZHM

CHARLES'f-T TUTTLE y 7, 1938. I. H. IHM ET AL 2,117,327-

' BORING MACHINE Filed March 12, 1935 2 Sheets-Sheet 2 llI||||IllI|II|Iilllllllllllllllllllllllll 111128 11013 IVA/V H [HM CHARLES F TUTTLE Patented May 17, 1938 BORIN G MACHINE Ivan H. Ihm and Charles'F. Tuttie, Richmond, Calif., assignors to Standard Oil Company of California, San Francisco, Calif., a corporation of Delaware Application March 12, 1935, Serial No: 10,622 I 2 Claims.

This invention relates to a boring machine and more particularly to a boring machine tool which is adapted to be used for resurfacing and similar operations in restricted bores of heavy and rela-' I tively immovable equipment, such as pressure still headers which may be in place in a furnace.

Heretofore, it has been the practice, when machining operations are required'on the grooves and the like of equipment such as pressure still headers, to 'remove them from their place in the furnace, and take them to a machine shop, where the machining is done. Inasmuch as these fittings are normally fixedly supported in the furnace and are further secured as firmly as possible to the tubes, to prevent leakage and blowing off due to internal pressure, this is ,a very expensive and inconvenient, as well as time consuming procedure. Certain types of alloy tubes are severely weakened and damaged by the heating which usually accompanies header removal, and in some cases where the tubes ,are welded to the headers,

- the tubes must be cut and destroyed, or at least shortened, before the headers can be taken off.

It is an object of this invention to provide a portable means-for doing accurate field machine boring, and the like in heavy and relatively immovable equipment, such as pressure still headers.

Another object is to provide a means for accurately aligning and positioning a boring machine tool in a restricted bore to operate on the same.

Another object is to provide a compact and rugged cross-teed means for a boring tool of this type. I

Another object is to provide a simple and accurate portable boring machine and guide means therefor adapted to remachine restricted bores.

These and other objects will be further apparent from the following description and from 40 the appended drawings, which form a part of this specification and illustrate an example of a preferred embodiment of this invention. In the drawings: i

Figure 1 is a side elevation view of a boring tool 4 in place in, a header and adapted to remachine the grooves into which the tube is expanded.

Figure 2 is a.vertical sectional view on line II-II of Figure l, and illustrates the tool holding, feeding, and guiding means of this embodiment. h

on line III-Ill ofFigure 2.

Figured is a top view of the tool post used in these examples. c 7

Figure 5 is an end view and Figure 6 a bottom Figure 3 is a vertical longitudinal sectional view view of the keyed feed bar used in these examples. Referring to the drawings and particularly to the grooving tool embodiment shown in Figures 1, 2 and 3, the numeral l0 indicates a header, diagrammatically shown here in section and provided with the usual tubeseat bore H, with grooves l 2, and I 3, into which a tube may be rolled or expanded into .place in the conventional manner. The tapered seat l4, into which a cap or plug closure for the header is adaptedlto seat, forms with the tube seat, a restricted bore, which makes accurate machining operations on the grooves i2 and I3 particularly diflicult.

The body l5 of the tool is generally cylindrical in shape and is provided with a turning or drive bar I6 which may be secured thereto permanently, or detachably as by'the squared end I! which is received in a corresponding square recess iii. A guide bushing l9 substantially surrounds body l5 and is preferably collapsible, in this case being made in three or more segments as shown, and is adapted to be first inserted in bore II in parts, and then assembled by means of spring wire retainers 20, which are snapped into grooves 2!. It will be noted that the bushing subtends only about 300 of the body I 5, in order to allow the cutting tool and the holder therefor to be extended radially to reach groove l2 or l3. This proportion has been found adequate to center the body IS in bore II.

Bushing I 9 is carried around. with tool body l5, by means of the longitudinal key 22 which is secured in a key seat 23 in the body. The periphery of bushing I9 is provided with a raised portion or ring 24, which engages groove l2, and aligns the bushing longitudinally in bore ll. There are two notches 25 and 2G, in the trailing or driving edge of bushing l9, notch 25 being aligned with, or at least spaced from, groove I 2, and notch 2.6 located in the same relation to groove l3. A lug 21 on key 22 engages either notch and aligns body I5 in bushing I 9 to operate on whichever groove is to be machined.

The cutting tool 28, for accomplishing the machining is secured in a generally cylindrical tool post or holder 29, as by set screws 30, 3i and 32. Holder 29 is received in a transverse bore 33 in body I 5, and is movable longitudinally in said bore by means of inclined grooves 34 in which are received complementary inclined teeth 35 on a cylindrical feed bar or element 36 (Figures 4, 5 and 6.)'

Feed bar 36 is positioned in longitudinal bore 31 in body l5 (Figures 2 and 3), and is prevented from rotating therein by a key 38, received in ure 1) to a point where both are accessible out-v side oi header I0. Spacers 48 are provided to align and support feed screw extension member 41 and drive bar 16, the former being retained longitudinally therein by collars 49, and also being adapted to be rotated in spacers 48, which in turn are secured to bar l6.

In operation, guide bushing i9 is first set into bore II, with ring 24 engaging groove l2. Body I5 is then inserted in bushing l9 and rotated to engage lug 21 on key 22 in notch 25 of bushing it, if groove I2 is to be deepened. If-groove I3 is to be operated on, lug 21 is engaged in notch 20. Cutting tool 28 is then moved outwardly into operative position by rotating feed screw 4i, which, by virtue of-its threaded engagement with the keyed feed bar 36fmoves the latter longitudinally in bore 31, thus sliding tool holder 29 transversely due to the interaction of inclined teeth 35 in grooves 34.

In one example, with a tooth and groove angle A" (Figures 4 and 6) of about 21 degrees 48 minutes and 5 seconds, which is a slope of 4.80

inches in 12 inches, and with a feed screw having 10 threads per inch, the tool was moved outwardly from body IS a distance of 0.040 inch for each complete turn of the feed screw. Thus by rotating body l5 through the medium of drive bar IS, with a periodical partial rotation of the feed screw extension member 41, the machining of grooves H or l3 in bore ll of the header l0 may be carried out uniformly, accurately, and to the depth desired.

' It will be appreciated that this invention is adapted to other uses than that given, and may be described as involving a rotatable body carrying a generally transversely movable tool post and cutting tool, with means extending from said body for moving the tool post as may be required, and means for centering the body and also for guiding it in the path which it is desired the tool will take. While a specific construction has been described and illustrated'to carry out these operations and functions, it is to be understood that the invention is not limited to that device, and all such modifications and changes as come within the scope of the appended claims are embraced thereby.

We claim:

1. A tube seat grooving-tool comprising a body, a radially extensible cutter onsaid body, a guide means for said body comprising a longitudinally split bushing adapted to be received within said tube seat and to engage a groove therein, means for holding said bushing in place in saidtube seat prior to the insertion of said body, and means selectively connecting said body and said guide means to space said body and said cutter longitudinally in said tube seat with regard to the groove engaged by said guide means.

2. A tube seat grooving tool according to claim 1 in which said bushing substantially encircles said body to align it centrally in said tube seat.

IVAN H. IHM. CHARLES F. TU'I'I'LE. 

